This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
The disadvantage of the deliquescent character of potash may be obviated, and its efficacy rather increased by combination with caustic lime, two parts of the latter to one of the former constituting "Vienna paste;" it should be kept dry, and moistened only with a little spirit as required. Epithelioma affecting the lip has been sometimes cured by successive applications of this caustic, but it is painful and tedious. The chlorate, given internally and applied locally, has also been said to arrest and cure epithelioma and certain Paris surgeons especially have reported well of the local use of concentrated solutions. I have observed several cases treated in this manner, but without substantial benefit. Uterine Ulceration. - Pure caustic potash has been applied to ulcerations and hyperplasiae of the cervix uteri, and although disastrous results, such as contraction and cicatrix have occasionally followed, it may be of decided service, in skilled hands, not only for irregular ulcerative conditions, but also in chronic cervicitis with induration (areolar hyperplasia); in such cases it may be applied about every ten days for several times, and free injections of vinegar and water should be used afterward. Dr. Henry Bennet recommended it or the lime compound "as a last resource," and the Vienna paste is sometimes serviceable. French surgeons use the same remedy, with an additional quantity of lime, carefully prepared in lead or iron tubes (caustic of Filhos, of Robiquet).
Urethral Stricture has been treated by the application of caustic potash to the affected part, and in some cases of cartilaginous hardness, and of unusual irritability, it apparently proved useful - with due precautions -but the majority of modern surgeons rightly, I think, object to any direct caustic application in such cases.